Almost everywhere convergence of Bochner-Riesz means with critical index for Dunkl transforms

Let B R ? ( h ? 2 ; f ) , ( R 0 ) denote the Bochner-Riesz means of order ? - 1 for the Dunkl transform of f ? L 1 ( R d ; h ? 2 d x ) associated with the weight function h ? 2 ( x ) : = ? j = 1 d | x j | 2 ? j on R d , where ? : = ( ? 1 , ? , ? d ) ? 0 , ∞ ) d . This paper shows that if ? ? 0 , then the Bochner-Riesz mean B R ? ( h ? 2 ; f ) ( x ) of each function f ? L 1 ( R d ; h ? 2 d x ) converges almost everywhere to f ( x ) on R d at the critical index ? = λ ? : = d - 1 2 + ? j = 1 d ? j as R ? ∞ . As is well-known in classical analysis, this result is no longer true in the unweighted case where ? = 0 , h ? ( x ) ? 1 , and B R ? ( h ? 2 ; f ) is the Bochner-Riesz mean of the Fourier transform.

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